This invention relates to a check valve of the type employed in fluid circuits for relieving excess pressures occurring therein. Conventional check or relief valves normally comprise a valve member reciprocally mounted in a housing and normally biased onto a seat thereof by a compression coil spring. When system pressures exceed a predetermined level, the valve member will open to relieve such pressures. Means for selectively adjusting the closing force on such valve member are oftentimes employed, as exemplified by the valve adjustment means disclosed in U.S. Pat. No. 3,550,617, assigned to the assignee of this application.